The Gamefaqs insider that informed us of this BDFF localisation has just shared some juicy bits about Versus XIII.

I believe I've already talked about Versus didn't I?

It's been plagued by internal politics strife but is on track for a late 4th quarter 2013 or early 2014.

From what I've seen, it's a gutted project into which far too much money and time has been poured into. Regarding an official announcement, nothing is planned just yet but we are already ramping up partnerships with distributors/retailers.

Calling versus a numbered title is debatable at this point.
Anyways some reveals are planned for the TGS (mid september), as for E3 nothing much concerning Versus.

As I said in another topic, they're not even considering localisation as it stands now.
Japan first, we'll see later. Hardly a forward-thinking way of doing things.

Regarding the length of marketing campaigns there's no set rule. It pretty much depends on your definition of campaign. As far as I'm concerned, it takes about 1 year including planning for AAA titles and can take as little as 2 months for smaller projects overseas.

As for it conflicting with Lightning Returns. Not really. The tentative deadlines (Yes, such things do exist, as stupid as this may sound) are far from being too restrictive. Late 4th quarter is the most optimistic one for the game to be ready to ship. (Emphasis on ready.)

My educated guess from the info I have is that late 1st quarter is a far more likely release date. The fighting goes on here and some of the big players aren't too happy with the amount of money this has been costing them. Don't forget that they are pretty much aware that FFXIII versus has been an embarrassment for them worldwide. They don't want to ship a half baked product for this one, now that would truly make them a laughing stock.